Apparatus for use in refining of lead bullion and similar operations



cs. K. WILLIAMS APPARATUS FORfUSE IN REFINING OFLEAD BULLION AND SIMILAROPERATIONS Filed Feb. 9, 1927 Patented Get. 9, 1928.

unites STATES PATENTOFFICE.

GEORGE KENNETH VIILLIAMS, 01? PORT PIRIE, SOUTH AUSTRALIA, AUSTRALIA.

APPARATUS FOR USE Application lead bullion and similar operations andrefers more especially to apparatus for the refining of lead bullioncontainin other metals such as copper or gold or silver or mixturesthereof. 7

Though this invention is herein described as adapted and used for therefining of lead bullion it will be understood that. it is alsoapplicable to the treatment of other liquid systems wherein certainconstituents or substances (sometimes in the form of impurities) areremoved by subjecting the same to differential temperatures.

This invention is especially adapted for the refining of lead bullion bysuch processes wherein Zinc is incorporated with the said bullion fortheformation of certain alloys of the said metals with zinc (with orwithout leac such as the lEarkes process wherein crusts are formedcomprising alloys of the said metals with zinc (with or without lead) orprocesses for the enrichment of the said crusts contained in theaforesaid Parkes HOCQ-SS or for the refining of bullion whereinSlllllClGIlt quantity of Zinc is incorporated with the said crusts orthe said bullion -and the same is maintained at the required temperaturefor the formation of molten layers of conjugatesolutions, the upper lay-.er of which comprises an alloy with zinc of other metal or metals andthe lower layer of bullion, which, if desired, can be cooled to itseutectic temperature producing residual bullion relatively low in suchmetals.

The invention is also applicable to the operation known as liquation asapplied to the crusts formedby the aforesaid larlres process in whichthe said crusts are heated for the removal of excess lead.

In addition theiinvention is applicable to s the preliminary treatmentto which lead bullion is usually subjected for the removal of the majorportion of the copper contained therein, wherein the temperature 0 theliquid bullion is lowered causing the copper or compounds of copper toseparate out due to the decreased solubility thereof in lead at suchlower temperatures.

In the refining of bullion as at present practised, it is customary tomaintain the said bullion in a molten condition in comparatively shallowopen vessels known as kettles, which are set in thene'cessary brickwork,

IN REFINIKG OF LEAD BULLION AND SIMILAR OPERATIONS.

filed February 9, 1927, Serial '0. 166,987, and in Australia March 6,1926.

. cooling the same around the bottom and the sides. In some casesreverberatory furnaces are used for certain treatment of lead bullion. i

In the refining of bullion containing alloying metals, it is'necessarythat the bullion should be heated to a certain tempera,- ture and theneither a portion thereof or the whole cooled to a certain temperature,and these open kettles being relatively broad and shallow do not welladapt themselves to these conditions, nor are the said kettles adaptedfor continuous treatment when re-' latively large tonnages are required.These objections also apply to reverberatory furnaces.

Now the object of this invention is to provide an apparatus for use inthe retining of lead bullion and similar operations wherein the bullionor other material being treated is more effectively subjectedto'differential temperatures such apparatus being especially adapted forthe refining ofbullion or the enrichment of Parkes crusts by continuoustreatment. By operating in an apparatus in accordance with thisinvention a continuous inflow of bullion may be maintained at the topand a continuous outflow of treated or residual bullion from the bottomand either a continuous or periodic re- .moval of the crusts orconjugate solutions formed, comprising the alloy desired to be removed.

I accomplish these objects by providing a vessel within which adeepnarrow column of molten metal may be maintained having means wherebydili'erent temperatures may be applied to different portions thereof.

. The apparatus constructed in accordance with this invention comprisesone or more deep narrow kettles-that is so say, kettles inwhich thedimensions are such that the depth is greater than the diameter incontra-distinction from the usual open shallow f kettles which areusually approximately hemispherical in shape. The kettles may be of anyconvenient shape, vthat is to say, they may be circular or oval in.cross section and may be either straight sided or tapering or s'tepwisethat is, of diifering diameters decreasing or increasing downwardslThese kettles may be arranged as single units or in series in suchmanner that the metal may flow from the discharge of one tothe feed on pof the other when continuous treatment is desired. Means are providedfor maintaining different portions of these kettles at differentialtemperatures that is to say, a relatively high temperature at the topand a relatively low temperature at the bottom and in some caseswherethe temperature of the bottom is at or about the eutectic of the metalthereina slightly higher temperature at the discharge orifice than atthe bottom. Any suitable means may be adopted for this purpose, such asan electrical heating medium, but for practical metallurgical purposes Iprefer the mounting of the kettles in brickwork having suitable fluesprovided with burners for liquid or gaseous fuel so that any portion ofthe kettle may be beat 'ed to a relatively high temperature and anotherportion to a relatively low temperature by adjusting the burners at thatportion or by circulating cool air around that portion if necessary.

In order that this invention may be more clearly understood referencemay be had to the accompanying sheet of drawings wherein an apparatus isillustrated adapted more especially for the refining of lead bullion,though not confined thereto. In these drawings- Figure 1 is a view insectional elevationof an apparatus constructor and arranged inaccordance with this invention.

Figure 2 is a planview in section of a part of Figure 1 taken on theline 22.

Fi ure 3 is a plan viewin section of a part of Figure 1 taken on theline 33. v Figures 4 and 5 are vertical sections of a portion of akettle showing the accommodation of means for ensuring the admixture ofthe metals.

The apparatus embodying this invention oreferabl consists of one or morelone narrow vessels 10 made of cast iron or other suitable materialcapable of resisting the necessary temperature to which they aresubjected. Figure 1 illustrates a two of these kettles 10. These kettlesare formed open at the top and are preferably provided with means forcontinuously or intermittently removing the molten metal from thebottom. For this purpose the said kettles may be provided either with asuitable tapping hole or with upwardly projecting spouts 13, the upperlips 14 of which are preferably below the upper rims of the kettles 10,and, if desired, these upwardly projecting spouts may be provided with anumber of tapping outlets so that the height of the overflow lip thereofmay be regulated and adjusted to suit requirements.

Means are provided for subjecting the saidvesselto differentialtemperatures, such as by providing two or more circular or surroundingflues 11 and 12 around different portions of the kettle. These lines lland series of burner'l5 for liquid or other fuel is pro vided. As at thelower portions of the kettle a relatively low temperature is usuallyrequired, such as the eutectic temperature of the residual bullion, theflue or lines 12 surrounding the lower portions of the kettle or vesselmay, in addition to means for supplying heat thereto, such as a burnerl6having means for cooling the same, such as circulating cold air or waterpipes, the said lues 12 being cut off from themain tlues for the timebeing by means of a suitable damper. As in some operations the bullion,the point of entry into the discharge orifice or spout 13, may be justat the eutectic temperature of the residual bullion, to prevent the samefreezing and thus obstruct the continuous flow of the bullion, the sailoutflow pipe or spout 13 may be provided with an independent surroundingflue 17 having a burner 18 whereby heat may be applied thereto and aslightly higher temperature maintained within the said spout 13. p

The kettle may be cast in one piece. Hovever, as the upper'portion ofthe kettle or vessel is maintained at a considerably higher temperatureit is, therefore, more liable to deterioration and cracking. I thereforepreferably form the vessel in two or more parts havin flanges 19 may beboltedor fastened together, so that the upper portion may be renewedfrom time to time without having to dismantle or discard the lowerportion. For the purpose of maintaining a relatively metal-tight jointthe two flanges 19 and 20 are pre ferably formed with a circular orconcentric groove 21 within which a circulating water pipe 22 isaccommodated, so that any metal entering the said joint is frozen andleakage avoided, or suitable packing may be provided in the groove 21.

in order that the temperature of the bullion at the lower end of thecolumn maybe accurately determined the kettles l0 preferably providedwith inclined pipes or tubes 10" adapted to accommodate suitablepyremeter couples.

By means of a kettle of this description the refining of lead bullioncontaining alloymetals may be effected as a continuous operation, thebullion being fed into the open mouth at the top together with suchamount of zinc as may be necessary for the is relatively free from suchmetals.

formation of the particular alloy required, the residual bullion beingallowed to over flow continuously from the spot 13 whilst the alloyformed may be removed either continuously or periodically from the upperportion ofthe kettle in the form of crusts or conjugate solutionaccording to the nature of the operation.

The drawings illustrate one particular adaptation of-the inventionwherein the bullion to be purified is passed through two kettlesarranged in series but it will be obvious to anyone skilled in the artthat the kettles may be used independently or the kettles may bearranged in various ways. I

For example alloys of certain metals may be preferentially removed inthe first kettle and the bullion discharged therefrom and passed to thesecond kettle in which alloys of other metals may be removed and ifneces sary through further kettles until the residual bullion dischargedfrom the last kettle In Figure 1,1 have shown a series of two kettles 10so arranged that the discharge spout 13 of the upper kettle deliversinto the top of the lower kettle. Such an arrangement is especiallyadapted for continuous treatment of bullion for the differential removalof alloying metals contained therein. In such treatment the bullion iscontinuously fed into the top of the upper kettle where a requisiteamount of zinc is incorporated and the requisite degree of heatmaintained for the formationof a conjugate solution comprising an alloyrelatively high in certain metal or metals. The lower portion of thisupper kettle is maintained at such a teniperature that the bulliondischarging from the spout 13 and delivered into the top of the lowerkettle is relatively low in such metals. The bullion discharging intothe top of the lower kettle is incorporated withthe requisite amount ofZinc and the temperature is maintained thereat at the requisite degreefor the formation of a conjugate solution relatively high in theremaining alloying metal or metals. By maintaining the lower portion ofthe second kettle at a temperature just above the eutectic of theresidual bullion and the temperature of the spout 13 just above thattemperature residual bullion relatively low mall the metals may be dis-I charged from'the spout of the second kettle.

The alloys or crusts formed in the upper portions of the two kettles maybe removed either continuously or periodically as may be required.

When the incorporation of the zinc with the bullion in the upper portionof the kettle effected bycausing the said bullion to pass down throughalayer of molten zinc (or an alloy high in zinc) means may be providedfor ensuring complete admixtures and for this purpose a rotating stirrer23 mounted on a spindle 24 accommodated within a cylinder 25 may beprovided as shown in Figure 4 or alternatively baffle plates or trays 26having staggered openings maybe provided as shown in Figure 5. Thesetrays or baflle plates may be mounted upon a vertical shaft 27 so thatthey may be moved or adjusted operation. I

By means of a kettle of this description the treatment of crustsobtained in the Parkes process for the purpose of enriching the same maybe effected as a, continuous operain height or position as required inthe tion, the crusts being fed into the open periodically orcontinuously, as may be desired, in the form of crusts, or of conjugatesolutions, or of a mixture of conjugate solution and dross or crusts,according to the quantity of infusible material present in the cruststreated and the degree of temperature maintained in the upper portion ofthe kettle. I

The operation of refining lead bullion'in an apparatus of thisdescription may-be effected in an exceedingly simple and eflicientmanner, with a saving in operating costs as compared with the kettles asat present in use. I

This invention is also adapted for the preliminary treatment of leadbullion for the separation of copper (which is usually effected in'reverberatory furnaces) prior to refining in which the bullion'at arelatively high temperature cooled to a relatively low temperaturecausing copper or compounds of copper to separate out due to theirperature.

The invention is also adaptable for the 7 treatment of other metals ofsubstances than lead bullion by methods which involve the maintenance ofa liquid system and subjecting the'same to differentialtemperatures forthe separation or removal of other metals or. compounds containedtherein.

I claim 2- 1. An apparatus for use in the refining of lead bullion andsimilar, operations comprising a' vessel within which a deep narrowcolumn of molten material may be maintainedhaving means wherebydifferent temperatures may be applied at different por-- 'tions thereofand means for independently wlthdrawing products from'at or about thetop and at or about the bottom thereof.

2. An apparatus for use in the refining of lead bullion and similaroperations comprising a deep narrow kettle having a plurality of finessurrounding different portions thereof at varying heights with means formaintaining different temperatures in the said fines and means forindependently withdrawing products from at or about the top and at orabout thebottom thereof.

'8. An apparatus for use in the refining of lead bullion and similaroperations eomprising a deep narrow kettle mounted in suitable brickworkhaving a series of fines surrounding different portions thereof withmeans for maintaining different temperatures in the said fiues and meansfor removing the molten metal from the lower portion of the said kettle.

l. An apparatus for use in the refining of lead bullion and similaroperations comprising-a deep narrow kettle having means for applyingdifferent temperatures to different portions thereof a discharge spoutleading from the bottom of the said kettle, the upper lip of which is ata lower level than the upper rim of the said kettle and means formaintaining said spout at the requisite temperature.

5. An apparatus for use in the refining of lead bullion and similaroperations comprising a deep narrow kettle mounted in suitable brickworkhaving an upper flue surrounding the upper portion thereof, a burnerarranged within the said flue for heating that portion of the kettlesurrounded there by, a lower flue surrounding the lower portion of thekettle having means for maintaining the same at the requisitetemperature, a discharge spout leading from the bottom of the saidkettle and a separate flue surrounding the. said discharge spout havingmeans for maintaining the said spout at the requisite temperature.

6. An apparatus for use in the refining of lead bullion and similaroperations comprising the combination with a deep narrow kettle havingmeans for maintaining the same at different temperatures at differentportions thereof, of means for effecting the admixture of the bullion orother 1118," terial passing therethrough.

7. An apparatus for use in the refining of bullion and similaroperations comprising the combination with a deep narrow kettle havinmeans for maintaining, the same at di erent temperatures at differentportions thereof, of a series of baflie plates or trays having staggeredopenings mounted in the upper portion of the said kettle for effectingthe admixture of the bullion or other material passing therethrough.

means for maintaining a relatively low temperature to the saidlower-portion of the kettle and a discharge spout leading from thebottom of the said kettle having means for ma ntaining the said spout atthe desired temperature. 7

9. An apparatus for use in the refining.

of lead bullion and similar operations comprising a number of'kettlesmounted in suit able brickwork and arranged in series in such. a mannerthat the discharge of one is delivered into the feed of the other exceptthe last in the series, said brickwork having separate fiues' arrangedin such a manner that the upper portions of the said kettles aremaintained at a relatively high temperature and the lower portion of thesaid kettle at a relatively low temperature, each kettle having adischargespout adapted to deliver the metal from the bottom thereof withmeans for maintaining the said spouts at the temperatures required. a

In w tness whereof I hereunto affix my signature. I

GEORGE KENNETH WILLIAMS.

